

Wynne is encountered during the crisis at the Circle of Magi. Returning Sten's sword secures his loyalty, if you choose to do so - this is really down to whether your Warden can take a morally relativistic view of Sven's crimes. If you do recruit him, you'll discover that his anger at breaking his code, the Qun, led him to murder some farmers who discovered him after he was parted from his sword. If you free him, you may then choose not to recruit him - at which point he departs from the game. It depends whether you're a rogue, nice, or a dick, basically.

You also have a few options for freeing him: pick the lock, or persuade/intimidate the Revered Mother of Lothering's Chantry. If left in the cage, he'll die when darkspawn destroy the village. Sten is a grey-skinned Qunari warrior discovered in a cage outside of the village of Lothering.

Everybody else has the option to recruit while at Ostagar. Human noble Wardens recruit their dog (such as you can ever recruit a dog to do anything) during their origin story.
